Women Are Better Connected... Neurally

The search for differences between the brains of men and women has a long and rather confusing history. Any structural differences are small, and their significance is controversial. The one rock-solid finding is that men's brains are slightly bigger on average. Then again, men are slightly bigger on average in general.

A new paper just out from Tomasi and Volkow (of cell-phones-affect-brain fame) offers, on the face of it, extremely strong evidence for a gender difference in the brain, not in structure but in function: Gender Differences in Brain Functional Connectivity Density.

Here's the headline pic:
They used resting-state "functional connectivity" (though see here for why this term may be misleading) fMRI in men and women. This essentially means that they put people in the MRI scanner, told them to just lie there and relax, and measured the degree to which activity in different parts of the brain was correlated to activity in every other part. They had a whopping 561 brains in total, though they didn't scan everyone themselves: they downloaded the data from here.

As you can see the results were highly consistent around the world. In both men and women, the main "connectivity hub" was an area called the ventral precuneus. This is interesting in itself although not a new finding as the precuneus has long been known to be involved in resting-state networks. However, the degree of connectivity was higher in women than in men 14% higher, in fact.

The method they used, which they've dubbed "Local Functional Connectivity Density Mapping", is apparantly a fast way of calculating the degree to which each part of the brain is functionally related to each other part.

You could do this by taking every single voxel and correlating it with every other voxel, for every single person, but this would take forever unless you had a supercomputer. LFCDM is, they say, a short-cut. I'm not really qualified to judge whether it's a valid one, but it looks solid.

Also, men's brains were on average bigger, but interestingly they show that women had, relative to brain size, more grey matter than men. Here's the data (I'm not sure about the color scheme...)

So what does the functional connectivity finding mean? It could mean anything, or nothing. You could interpret the highly interconnected female brain as an explanation for why women are more holistic, better at multi-tasking, and more in touch with their emotions than men with their fragmented faculties. Or whatever.

Or you could say, that that's sexist rubbish, and all this means is that men and women on average are thinking about different things when they lie in MRI scanners. We already know that resting-state functional connectivity centred on the precuneus is suppressed whenever your attention is directed towards an external "task".

That's not a fault of this research, which is excellent as far as it goes and certainly raises lots of interesting questions about functional connectivity. But we don't know what it means quite yet.

Tomasi D, & Volkow ND (2011). Gender differences in brain functional connectivity density. Human brain mapping PMID: 21425398

Women Are Better Connected... Neurally

The search for differences between the brains of men and women has a long and rather confusing history. Any structural differences are small, and their significance is controversial. The one rock-solid finding is that men's brains are slightly bigger on average. Then again, men are slightly bigger on average in general.

A new paper just out from Tomasi and Volkow (of cell-phones-affect-brain fame) offers, on the face of it, extremely strong evidence for a gender difference in the brain, not in structure but in function: Gender Differences in Brain Functional Connectivity Density.

Here's the headline pic:
They used resting-state "functional connectivity" (though see here for why this term may be misleading) fMRI in men and women. This essentially means that they put people in the MRI scanner, told them to just lie there and relax, and measured the degree to which activity in different parts of the brain was correlated to activity in every other part. They had a whopping 561 brains in total, though they didn't scan everyone themselves: they downloaded the data from here.

As you can see the results were highly consistent around the world. In both men and women, the main "connectivity hub" was an area called the ventral precuneus. This is interesting in itself although not a new finding as the precuneus has long been known to be involved in resting-state networks. However, the degree of connectivity was higher in women than in men 14% higher, in fact.

The method they used, which they've dubbed "Local Functional Connectivity Density Mapping", is apparantly a fast way of calculating the degree to which each part of the brain is functionally related to each other part.

You could do this by taking every single voxel and correlating it with every other voxel, for every single person, but this would take forever unless you had a supercomputer. LFCDM is, they say, a short-cut. I'm not really qualified to judge whether it's a valid one, but it looks solid.

Also, men's brains were on average bigger, but interestingly they show that women had, relative to brain size, more grey matter than men. Here's the data (I'm not sure about the color scheme...)

So what does the functional connectivity finding mean? It could mean anything, or nothing. You could interpret the highly interconnected female brain as an explanation for why women are more holistic, better at multi-tasking, and more in touch with their emotions than men with their fragmented faculties. Or whatever.

Or you could say, that that's sexist rubbish, and all this means is that men and women on average are thinking about different things when they lie in MRI scanners. We already know that resting-state functional connectivity centred on the precuneus is suppressed whenever your attention is directed towards an external "task".

That's not a fault of this research, which is excellent as far as it goes and certainly raises lots of interesting questions about functional connectivity. But we don't know what it means quite yet.

Tomasi D, & Volkow ND (2011). Gender differences in brain functional connectivity density. Human brain mapping PMID: 21425398

Commemorating the Civil War

In two weeks our university is going to commemorate the 150^th anniversary of the beginning of the American Civil War. Students and faculty members are invited to bring the mementos of Civil War that belong to their families. They are also urged to abstain from bringing any of their heirloom firearms to the exhibition of mementos.

Recognized

I was walking around campus right now, and a student I don't know stopped me. 

"Oh, you are Professor Clarissa!" she said. "My friends took classes with you and they loved you. I wish I could take your classes too but my program is too full."

It was very nice to know that after only 3 and a half semesters here I'm already getting recognized on campus. And, more importantly, not for anything negative.

And we have 14,000 students, in case you were wondering, so it isn't a tiny little place or anything. 

Need to Grumble

It's one of those days when one would be much better off staying in bed and not moving at all because everything comes out wrong. First, I attempted to show a movie in my class and, of course, the same idiot who always disconnects the stupid equipment disconnected it again. Which meant that I had to crawl around on the floor messing up my clothes and shoes for 15 minutes trying to connect the equipment. And I have no doubt that when I show up for the second section of this course later today, it will all be disconnected yet again.

After I managed to get the movie to start playing, I remembered that there was a sex scene in it. I had forgotten about the scene completely because I find it to be so innocent as to be fit to show to children of any age, let alone university students. So now I have no idea whether it would be considered appropriate by my Bible Belt students. The movie is called Butterfly. In case you are curious, you can watch this scene in the following video. If you do, please tell me whether it was a horrible idea to show it in class. It only lasts about 4 minutes altogether.

After the class, I remembered that I'd forgotten to have breakfast so I decided to have lunch. But the stupid University Restaurant had a pizza day today. Have you ever heard anything so ridiculous? Who on earth feeds professors with pizza for lunch?

It isn't yet noon and I'm already in a very grumbling mood.

Scholarly Base Maintenance Month

On his interesting and useful blog that helps people become research scholars, Jonathan Mayhew introduces the concept of scholarly base. This term refers to all the readings, all the knowledge that a scholar has accumulated in the course of his or her life. This is the kind of knowledge that one draws upon in one's research, that allows one not to feel stupid and lost at scholarly conferences, and that helps one to maintain a coherent picture of one's own field of study as well as several other fields that in some ways overlap with or border upon one's own research area(s).

A scholarly base needs to be maintained and expanded at all times because nothing is sadder than a scholar who works on the basis of limited and outdated readings that were done 20 years ago. I usually have my scholarly base maintenance month in the summer. This year, however, I have other things planned for the summer vacations, so my scholarly base maintenance month started this week. I have gathered a stack of books that need to be read before the end of the semester five weeks from now. Here are what these books are:

1. Three Latin American novels. As I was writing my recent blog post on Latin American literature, I discovered that my familiarity with it has grown pretty dim. To be completely honest, I read nothing new in this field since my doctoral comprehensive exams in 2005. So now I will be catching up using great reading suggestions from a fellow blogger who publishes her informative posts here.

2. Four books of philosophy (Badiou, Laclau, Bauman, and Eagleton).

3. Two books of literary criticism. Possibly I will write a review of one of them since it came out very recently.

4. Four books in my field of contemporary Spanish literature. There are several authors that I follow and some of them have recently released new books (most of which are extremely long, too.) 

The good news is that I read extremely fast, so I have no doubt all these books can be read by the end of the semester. I really can't wait to get into each one of them, so it will be a very fun month.

The readers of this blog should expect to be inundated with book reviews.

Inconscientemente, parecia querer buscar em autores, filmes e música, algum tipo de consolo. Como se alguém precisasse chegar perto de onde eu estava, colocar uma das mãos no meu ombro e dizer que aquilo era normal. Que acontecia também com outras pessoas. E que iria passar.

(Caio F. Abreu)